Vitamin E is a group of eight fat-soluble organic compounds (tocopherols and tocotrienols), which are referred to as the vitamin of youth. Vitamin E is an important nutrient for the proper functioning of the human body, as it acts as a powerful antioxidant and regulator of many metabolic processes. The human body cannot produce vitamin E on its own, so it must be supplied with the diet.

• What functions does vitamin E have in the human body?
• The body's requirement for vitamin E
• Vitamin E - dietary sources
• Vitamin E deficiency
• Vitamin E - effects of excess

What functions does vitamin E have in the human body?

Many people wonder what properties vitamin E exhibits and what effect its supplementation has on the human body. As it turns out, vitamin E is a well-known antioxidant that neutralizes the damaging effects of free radicals, so it can reduce the risk of developing a wide variety of diseases of civilization, including cardiovascular diseases (e.g. atherosclerosis of the blood vessels, coronary heart disease), neurodegenerative diseases (Alzheimer's and Parkinson's diseases), cancer (e.g. lung cancer, breast cancer) and ophthalmic diseases (cataracts). In addition, vitamin E ensures the proper functioning of male and female reproductive organs and immune system cells, and regulates intercellular signaling. Vitamin E has a beneficial effect on male fertility by increasing sperm concentration and improving sperm motility. Vitamin E also prevents damage to blood vessels, inhibits platelet accumulation and protects polyunsaturated fatty acids from oxidation. In addition, vitamin E has a beneficial effect on the skin, as it slows down the aging process, improves blood supply to the skin, and strengthens the connective tissue that makes up the dermis.

The body's requirement for vitamin E

The demand for vitamin E depends on such individual characteristics as age, gender and physiological state, as well as functional changes in the gastrointestinal tract. In addition, the demand for vitamin E is influenced by the type of food consumed, including the supply of other antioxidant vitamins and the type of fat consumed. Polish standards for vitamin E, set at the level of sufficient intake (AI), indicate that adult men should provide 10 mg of α-tocopherol equivalent each day, while adult women should provide 8 mg. Only during pregnancy and lactation should women provide a higher amount of vitamin E, 10 mg and 11 mg of α-tocopherol equivalent, respectively.

Vitamin E - dietary sources

Vitamin E is found in both plant and animal products. Its main dietary sources are vegetable oils, nuts, seeds, seeds, cereal products, meat, fish, milk and milk products, and some vegetables and fruits. Among the products containing the largest amounts of vitamin E are:

• vegetable fats, such as oils (among others: sunflower, safflower,
  canola, wheat germ, olive oil), soft margarine,
  butter.
• Nuts, e.g. almonds, hazelnuts, walnuts, peanuts.
• Seeds and seeds, e.g. sunflower seeds, sesame seeds, pumpkin seeds.
• Cereal products, such as wheat bran, oatmeal, wholemeal bread.
• Vegetables and fruits, such as: spinach, kale, broccoli, savoy cabbage,
  parsley, bell peppers, avocados, blueberries.

Vitamin E deficiency

Because vitamin E is commonly found in a wide variety of foods, vitamin E deficiency resulting from a poorly varied diet is relatively rare. One of the main factors that can actually lead to vitamin E deficiency is impaired intestinal fat absorption. In particular, patients with cystic fibrosis, short bowel syndrome, cholestasis (impaired outflow of bile from the liver to the duodenum) and exocrine pancreatic insufficiency have a higher risk of developing vitamin E deficiency. Vitamin E deficiency can cause hemolytic anemia, impaired vision, impaired coordination and balance, loss of proprioceptive sensation, partial abolition of reflexes, speech impairment, and the formation of blood clots and embolisms due to impaired platelet aggregation.

Vitamin E - effects of excess

Excess is found very rarely and only when taking vitamin E supplements. It is also characterized by low toxicity, since the human body has well-developed mechanisms to prevent its excessive accumulation. Excessive vitamin E can occur when the permissible maximum intake level, which is 300 mg per day for adults, is repeatedly exceeded. In contrast, a daily dose of vitamin E is considered a toxic daily intake of 2,000 mg. Excess vitamin E leads to inhibition of platelet aggregation and can cause hemorrhage. Hence, taking high doses of vitamin E in combination with anticoagulants or antiplatelet drugs can increase the risk of bleeding, and even more so when vitamin K intake is low. High doses of vitamin E may also increase the risk of developing heart failure and hemorrhagic stroke. In addition, it has been suggested that excess vitamin E may reduce the effectiveness of radiation and chemotherapy in cancer patients.

Sources:

• Jarosz M., Rychlik E., Stoś K. et al: Nutrition standards for the Polish population and their application. National Institute of Public Health - National Institute of Hygiene, 2020.
• Chen G, Wang J, Hong X, et al: Dietary vitamin E intake could reduce the risk of lung cancer: evidence from a meta-analysis. Int J Clin Exp Med. 2015 Apr 15;8(4):6631-7.
• Abner EL, Schmitt FA, Mendiondo MS, et al: Vitamin E and all-cause mortality: a meta-analysis. Curr Aging Sci. 2011 Jul;4(2):158-70.
• Schürks M, Glynn RJ, Rist PM, et al: Effects of vitamin E on stroke subtypes: meta-analysis of randomised controlled trials. BMJ. 2010 Nov 4;341:c5702.